Elevating COPD Management: Enhancing Treatment and Improving Patient Outcomes - Episode 4
The Utility of Blood Eosinophils and Other Emerging Biomarkers in COPD Management
Panelists discuss the growing role of blood eosinophils as a key biomarker in chronic obstructive pulmonary disease (COPD) management, highlighting their utility in guiding inhaled corticosteroid and biologic therapy decisions, the benefits of tracking longitudinal trends to improve accuracy, and the potential for integrating emerging biomarkers like FeNO to further personalize treatment despite current limitations.
The role of blood eosinophils in COPD management has become increasingly important in recent years, as awareness has grown around their potential to reflect an inflammatory phenotype. Clinicians are now more routinely using eosinophil counts from standard complete blood counts with differential to identify patients who may benefit from specific therapies, especially those with frequent exacerbations. While the exact cutoff remains debated—ranging from 150 to 300 cells/µL—the broader consensus is that higher eosinophil counts are associated with greater risk of exacerbations and worse disease progression. As a result, eosinophil levels now often guide decisions on initiating or escalating inhaled corticosteroid therapy, particularly in patients with poorly controlled symptoms.
In clinical practice, it’s become increasingly common to look retrospectively at a patient’s eosinophil trends over time rather than relying on a single measurement. This historical perspective helps account for confounders such as recent steroid use, which can suppress eosinophil levels, and provides a more reliable picture of a patient’s underlying inflammatory status. The ease and affordability of obtaining eosinophil counts, combined with their routine presence in lab panels, make them a particularly accessible biomarker. Moreover, their presence has been linked not just to exacerbation risk but also to potential response to biologics targeting type 2 inflammation, which is gradually reshaping how COPD is approached.
Despite their utility, blood eosinophils are not a perfect tool. Levels can fluctuate due to infections, medications, and comorbidities, making interpretation challenging. Still, they remain the most actionable biomarker currently available for COPD. Emerging tools like FeNO (fractional exhaled nitric oxide) are also under study, especially for their potential to predict response to IL-13 inhibitors, though practical limitations—such as variability with smoking—have prevented widespread adoption. Ultimately, as more therapies become available, integrating multiple biomarkers may enhance precision in managing COPD.
